Sample cups have to be hermetically closed preferably with a screwable cap in order to ensure that the sample contained therein cannot be contaminated by external agents and also in order to protect laboratory staff from the risk of being contaminated by a pathological sample which may be contained in the sample cup. This applies in general to sample cups used for clinical chemistry tests, and in particular to sample cups used in methods for isolating a nucleic acid sample from cell material.
According to the prior art the cap of such a sample cup has to be removed and replaced manually with great care in order to allow pipetting operations, e.g. for transferring a portion of a biological sample contained in a primary sample tube into the sample cup, before a method for isolating a nucleic acid sample from cell material is carried out on a sample contained in a sample cup; or for transferring a nucleic acid sample isolated by such a method into the sample cup.
The above mentioned manual removal and replacement of the screwable cap of sample cups is time consuming and is not compatible with the increasing need for automatic handling of sample cups in modern automatic sample cup handling apparatuses. There is therefore a need to automate the removal and replacement of the screwable caps.
There is moreover a need to transport individual sample cups closed with their respective screwable cap to different positions within the sample cup handling apparatus, e.g. in order to perform different steps of a method for isolating a nucleic acid sample from cell material.